Wearable devices include all various kinds of electronic devices that a user can wear on a user's body or clothes. The wearable devices may be, for example, a smart watch, a wearable computer, Google glasses, a Bluetooth headset, a smart wear, and the like.
Such a wearable device, as described above, is wearable on a user's body or clothes. Accordingly, if the wearable device is used, a various kinds of states related to the user's body can be measured. Currently, studies for enabling advantages of the wearable device to be more widely used are being actively conducted.